28 Oct Mercury Isotope Analysis
A new article using the NIC Model MA-3000 Mercury Analyzer for total mercury analysis and mercury isotope analysis was published earlier this year. The MA-3000’s usefulness for such analysis is detailed in the article, which can be downloaded by clicking here.
“Simultaneous combustion preparation for mercury isotope analysis and detection of total mercury using a direct mercury analyzer”
Maxime Enrico (a), Prentiss Balcom (a), David T. Johnston (b), Julien Foriel (b), Elsie M. Sunderland (a, b)
a Harvard John A. Paulson School of Engineering & Applied Sciences, Harvard University, 29 Oxford St, Cambridge, MA, 02138, USA
b Department of Earth and Planetary Sciences, Harvard University, 20 Oxford St, Cambridge, MA, 02138, USA
Abstract
Mercury (Hg) stable isotope signatures are widely used to understand Hg cycling in the environment. Sample preparation methods for determining Hg isotope ratios by CV-MC-ICP-MS vary widely among laboratory facilities and sample types. Here, we present a novel and rapid method for preparing solid samples prior to determining Hg isotope composition. We use a direct Hg analyzer (that measures total Hg) for sample combustion, amalgamation and analysis. During the thermal release of Hg from the amalgamator and following detection, the analyte gas enters a trapping solution consisting of 10% HCl/BrCl (5:1, vol/vol). We find Hg blank values are less than 1% of the Hg introduced during sample analysis, Hg detection is not altered by modifying the system, and more than 90% of the introduced Hg is recovered in the trapping solution. Hg isotope results are statistically indistinguishable from accepted values for previously published certified reference materials and uncertainty of 2s (0.05e0.12‰) is similar to the solution standard RM8610 (2s ¼ 0.09‰). This new method allows for solid sample preparation for Hg isotope analysis in under 15 min. It has the additional advantage of minimizing use of sample mass during simultaneous detection and preparation.